Pressure cooker

ABSTRACT

A pressure cooker comprises a handle, a body, an outer lid being pivotally mounted on the body, an inner vessel with flange extending radially, an inner lid that is configured to cover the inner vessel, a rotatable rim protrusions that selectively engages with the flange of the inner vessel. The pressure cooker that utilizes a one-hand opening and locking mechanism that simultaneously locks the outer lid with the main body and locks the inner lid with the inner vessel. The locking of the outer lid is achieved by a clasp assembly, whose position is controlled by the handle. The locking of the outer lid is achieved by the pairing of the flange and the rim protrusions, whose position is also controlled by the handle. The pressure cooker also comprises a pressure rod that changes its level based on the pressure of the inner vessel.

FIELD OF THE INVENTION

The present invention relates to household and kitchen appliances. Inparticular, the present invention relates to cooking devices. Even moreparticularly, the present invention relates to pressure-cooking deviceswith various safety features.

BACKGROUND

Pressure cooking refers to a method of cooking that utilizes the heatingof an enclosed and sealed cooking chamber. The pressure built up in thesealed chamber reduces the cooking time and changes the texture of thefood. This type of cooking is desirable in many situations because itoften saves time and energy.

However, pressure cookers also have their drawbacks. The main concernraised by pressure cooking is related to safety. One major safetyconcern is that users may be injured by the hot and pressurized steam ifthe users open the lid of the pressure cooker when the pressure is high.The hot and pressurized gas may be vigorously ejected from the cookerwhen the lid is opened.

Another safety concern is that the lids of pressure cookers may not besecured tightly enough. When pressure builds up inside such cookers,some lid designs may not withstand the high pressure. This again cancause severe injury to users if the lid is blown off when the internalpressure exceeds the tolerance of the lid. In some extreme cases, thepressure cooker itself could may explode. Another draw back is that somelids are not designs to carry the weight of the pressure cooker. Suchlid designs may be compromised over time when used repeatedly totransport the pressure cooker. Hence, when a user carries the cookerwith only one hand by the holding the handle of the lid, the lid sealmay be compromised, resulting in faulty performance.

As such, providing a convenient yet safe way to open and lock the lid ofa pressure cooker that addresses different safety concerns is always achallenge in designing pressure cookers. A lid that can be opened withone hand is often used in regular rice cookers but is rare in pressurecookers. While such a lid is convenient for users to open the lid, itnormally only relies on one locking mechanism that is usually not strongenough to withstand the pressure in a pressure cookers. Pressure cookersusually utilizes a two-hand locking method that requires users to firstscrew in the lid to the body of the pressure cooker by turning the lidseveral rounds, then lock the lid and body with an additional lockingmechanism. This design, despite normally being capable of withstandingthe pressure, is very inconvenient to use.

SUMMARY

It is an objective of the present invention to provide a pressure cookerthat is convenient and safe to use. It is also an objective of thepresent invention to provide a design that permits users to open apressure cooker with only one hand while not compromising the integrityof pressure cooker to withstand high pressure. It is a further object ofthe present invention to incorporate into a pressure cooker various newand novel combinations of safety and convenience features.

In one embodiment of the present invention, a pressure cooker comprisesa main body with a chamber therein; an outer lid that is pivotallymounted on the main body such that the outer lid can be opened or closedrelative to the main body; a handle; and an inner vessel that isconfigured to be removably placed within the chamber. The inner vesselhas a circumference with a flange extending radially from thecircumference. The flange may also have sections that are recessed sothat the flange varies in width about its circumference. On the bottomsurface of the outer lid, an inner lid is mounted and secured. A rimsurrounding the inner lid is also mounted on the outer lid but isrotatable in relationship to the inner lid. The inner lid is configuredto cover the inner vessel when the outer lid is closed. There are rimprotrusions that form a groove or slot under the rim. The slots areformed by the rim protrusions because the protrusions extend outwardfrom the rim a distance greater than flange of the inner vessel beforeextending down and inward under the rim. The radius of the rim is largerthan the radius of the inner vessel. The rim protrusions are configuredto fit into the recessed portions of the flange of the inner vessel sothat when the rim is rotated, the flange of the inner vessel slides intothe slot formed by each rim protrusion to snuggly secure the inner lidto the inner vessel.

In one embodiment of the present invention, the pressure cooker has anactuator mechanism comprising a rod, a handle, a locking arm, a safetyarm, and a support plate. The outer lid has an interior chamber thathouses the actuator mechanism. The support plate is located within theinterior chamber. In the preferred embodiment, the rod is rotatablysecured in the center of the support plate and extends upward to passthrough an aperture in the top of the outer lid. The handle is securedto the top of the rod, which makes the handle accessible to the userabove the outer lid. The locking arm and the safety arm are secured tothe rod within the interior chamber. In the preferred embodiment, threearcuate slits are formed in the support plate at an approximately equaldistance from each other. A primary attachment means is secured to thelocking arm at a position on the locking arm that permits the primaryattachment means to pass through one of the arcuate slits to be securedto the top of the rim, which is located below the support plate. Thisconfiguration permits the user to rotate the handle in order to rotatethe rim via the locking arm thereby locking the inner lid in placethrough the engagement of the rim protrusions with the flange of theinner vessel described above.

The other two arcuate slits in the support plate also have secondaryattachment means passing through them and are secured to the top of therim, but these secondary attachment means are not attached to anylocking arm. The two secondary attachment means slide freely in theother two slits, but include a feature, such as a bolt head or washer oranalogous device, that permits the secondary attachment means to bebiased against the top of the support plate to assist with stablerotation of the rim as the locking arm moves the rim into a lockedposition.

The safety arm of the actuator mechanism is positioned above a safetychannel in the support plate. The safety arm has a member that descendsinto the safety channel wherein the member can freely move within thelength of the safety channel if the internal pressure is at a level thatis safe for the cooker to be opened. The safety channel is positionedabove a pressure rod that is incorporated into the top of the inner lid.When the pressure in the inner vessel rises to a level that would makeit unsafe to open, then the pressure rod extends into the safety channelthereby blocking the safety arm member from moving. Since the safety armis secured to the rod, this means that the rod cannot rotate, whicheffectively prevents the locking arm from moving to the unlockedposition because the locking arm can only move in response to rotationof the rod. This mechanism prevents the user from opening the pressurecooker when the pressure inside renders it is unsafe to open.

The outer lid also has a clasp assembly that includes a spring assemblymechanism that biases the clasp assembly in the locked position. Theclasp assembly is configured to interact with the locking arm when theactuator mechanism moves to the open position such that the locking armapplies a force to the clasp assembly to overcome the force of thespring assembly that keeps the outer lid in a locked position. When theclasp assembly is in an unlocked position, then the outer lid may beopened.

The actuator mechanism has at least a first open position and a secondclosed position. At the first open position, the handle via the rod andlocking arm causes the rim to turn so that the rim protrusions alignwith the recesses of the flange of the inner vessel, thus allowing theinner vessel to be detached from the inner lid, and the locking armfurther causes the clasp assembly to be biased in an unlocked position.At the second closed position, the handle via the rod and locking armcauses the rim to rotate in the opposite direction so that the flange ofthe inner vessel slides into the groove of the rim protrusions, thuslocking the inner lid on top of the inner vessel. When the locking armrotates the rim into the locked position, the locking arm simultaneouslydisengages from the spring assembly, which causes the clasp assembly toreturn to a locked position in which the outer lid is also locked inplace. In another embodiment, the inner lid is traversed by a pressurerod. The pressure rod is configured so that it is pushed upward bypressure within the inner vessel during cooking. The pressure rodprovides an indication of the level of pressure in the inner vessel.

In yet another embodiment, the pressure cooker further comprises anelectromagnetic valve. The inner lid has an air-releasing assemblymounted on its upper surface. An air-releasing conduit is present withinthe air-releasing assembly. The air-releasing conduit traverses theinner lid such that air can go in or out of the inner vessel through theair-releasing conduit. A ball bearing is movably mounted within theair-releasing assembly. The ball bearing has a sealed position and areleased position. The air-releasing conduit cannot release pressurefrom the inner vessel when the ball bearing is at the sealed position,and can release pressure when the ball bearing is at the releasedposition. The electromagnetic valve controls the position of the ballbearing such that the electromagnetic valve can control the pressure ofthe inner vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a pressure cooker in accordancewith an embodiment of the present invention.

FIG. 2 is a rear perspective view of a pressure cooker in accordancewith an embodiment of the present invention.

FIG. 3 is a perspective view of a pressure cooker in accordance with anembodiment of the present invention when the outer lid is opened.

FIG. 4 is an enlarged view of the lower surface of the outer lid of apressure cooker in accordance with an embodiment of the presentinvention.

FIG. 5 is a perspective view of an inner vessel of a pressure cooker inaccordance with an embodiment of the present invention.

FIG. 6 is a top view of the inner vessel shown in FIG. 5.

FIG. 7 is an internal view of the interior of an outer lid of a pressurecooker in accordance with an embodiment of the present invention.

FIG. 8 is the top internal view of the interior of the outer lid shownin FIG. 7.

FIG. 9 is a side internal view of the interior of an outer lid of apressure cooker in accordance with an embodiment of the presentinvention.

FIG. 10 is an enlarged view of a certain section of the interior of theouter lid of a pressure cooker in accordance with an embodiment of thepresent invention with emphasis on the interaction between a actuatorrod and a clasp assembly.

FIG. 11 is another enlarged view of a certain section of the interior ofthe outer lid of a pressure cooker in accordance with an embodiment ofthe present invention with the actuator rod and the clasp assembly inFIG. 10 changed in position.

FIG. 12 is an enlarged side internal view of a certain section of theinterior of the outer lid of a pressure cooker a pressure cooker inaccordance with an embodiment of the present invention with emphasis onthe interaction between a actuator rod and a clasp assembly.

FIG. 13 is another side internal view of a certain section of theinterior of the outer lid of a pressure cooker in accordance with anembodiment of the present invention with the actuator rod and the claspassembly in FIG. 12 changed in position.

FIG. 14 is another internal view of the interior of the outer lid of apressure cooker in accordance with an embodiment of the presentinvention with emphasis on the interaction between a actuator rod and ahandle.

FIG. 15 is yet another internal view of the interior of the outer lid ofa pressure cooker in accordance with an embodiment of the presentinvention with the actuator rod and the handle changed in position.

FIG. 16 is an enlarged view of the flanges of an inner vessel of apressure cooker in accordance with an embodiment of the presentinvention with emphasis on the interaction between the flanges and therim protrusions.

FIG. 17 another enlarged view of the flanges of an inner vessel of apressure cooker in accordance with an embodiment of the presentinvention with the flanges and the rim protrusions changed in position.

FIG. 18 is an internal view of the outer lid of a pressure cooker inaccordance with an embodiment of the present invention showing a certainarea where a pressure rod is located.

FIG. 19 is another internal view of the outer lid of a pressure cookerin accordance with an embodiment of the present invention with theemphasis on the level of a pressure rod.

FIG. 20 is yet another internal view of the outer lid of a pressurecooker in accordance with an embodiment of the present invention withthe emphasis on the pressure rod shown in FIG. 19 at a different level.

FIG. 21 is another internal view of the outer lid of a pressure cookerin accordance with an embodiment of the present invention with theemphasis on the interaction of an actuator rod and a pressure rod.

FIG. 22 is yet another internal view of the outer lid of a pressurecooker in accordance with an embodiment of the present invention withthe emphasis on the interaction of a actuator rod and a pressure rod.

FIG. 23 is an isolated view of an inner lid and a rim of a pressurecooker in accordance with an embodiment of the present invention.

FIG. 24 is an isolated exploded view of the inner lid and the rim of apressure cooker shown in FIG. 23 in accordance with an embodiment of thepresent invention.

FIG. 25 is an illustrative view of an air-releasing assembly of apressure cooker in accordance with an embodiment of the presentinvention.

FIG. 26 is another illustrative view of an air-releasing assembly of apressure cooker in accordance with an embodiment of the presentinvention.

FIG. 27 is an illustrate side internal view a steam collecting assemblyof a pressure cooker in accordance with an embodiment of the presentinvention.

FIG. 28 is an illustrate exploded view of a team collecting assembly ofa pressure cooker in accordance with an embodiment of the presentinvention.

FIG. 29 is a side internal view of a pressure cooker in accordance withan embodiment of the present invention.

DETAILED DESCRIPTION OF EMBODIMENTS

The following description is made for the purpose of illustrating thegeneral principles of the invention and should not be taken in alimiting sense. The scope of the invention is best determined byreference to the appended claims.

The invention now will be described more fully hereinafter withreference to the accompanying drawings, in which embodiments of theinvention are shown. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theembodiments set forth herein. Rather, these embodiments are provided sothat this disclosure will be thorough and complete, and will fullyconvey the scope of the invention to those skilled in the art.

Exemplary embodiments of the present invention are described herein withreference to idealized embodiments of the present invention. As such,variations from the shapes of the illustrations as a result, forexample, of manufacturing techniques and/or tolerances, are to beexpected. Thus, embodiments of the present invention should not beconstrued as limited to the particular shapes of regions illustratedherein but are to include deviations in shapes that result, for example,from manufacturing.

Now referring to FIGS. 1 and 2, FIG. 1 shows a front perspective view ofan embodiment of the present invention 100. FIG. 2 is the correspondingrear perspective view of the same embodiment. The pressure cooker 100comprises a main body 102, an outer lid 104, a handle 106, a base 108,and a user interface 110. The main body 102 has a chamber 116 inside themain body 102. The outer lid 104 covers the chamber 116 so the chamber116 is not visible in FIG. 1. The chamber 116 is best shown in FIG. 29.The user interface 110 has buttons and display thereon for the users tocontrol the pressure cooker 100. A pressure indicator 112 and a steamvalve 114 are present on the upper surface 126 of the outer lid 104.

The outer lid 104 is pivotally mounted on the main body 102 by the joint118 in the back of the pressure cooker 100. As such, the outer lid 104can be pivotally opened or closed relative to the main body 102. FIG. 1is a view when the outer lid 104 is closed and FIG. 3 is a view when theouter lid 104 is open. At the top of the outer lid 104, the handle 106is rotatably mounted. The handle 106 comprises a rotary switch knob sothat the users can turn the handle 106 clockwise or counter-clockwise toopen or close the outer lid 104 in relation to the main body 102. Themechanism of turning the handle 106 to open or close the outer lid 104is discussed in further detail below.

FIG. 3 is a perspective view of the pressure cooker 100 when the outerlid 104 is open with an inner vessel 500 visible inside the pressurecooker 100. The inner vessel 500 can be removably placed within thechamber 116 of the main body 102. The inner vessel 500 is a container inwhich food is placed for cooking. The inner vessel 500 can be taken outfrom the main body 102 to be cleaned.

FIGS. 5 and 6 show isolated views of the inner vessel 500 in accordancewith a particular embodiment of the present invention. In thisembodiment, the inner vessel 500 is a cylinder receptacle with open top.On the outer wall of the inner vessel 500, there are two handles 504.The handles 504 serve at least two different purposes. First, thehandles 504 can act as handgrips for the users to hold the inner vessel500 when the inner vessel 500 is taken out of the pressure cooker 100.Second, referring back to FIG. 3, the handles 504 align the inner vessel500 with the chamber 116 such that, when the inner vessel 500 is placedinto the chamber 116, only certain orientations are allowed to preventthe inner vessel 500 from rotating inside the chamber 116. While in theembodiment shown, there are two handles 504, those skilled in the artwill understand that there could be one or any numbers of handles 504 torestrict the rotation of the inner vessel 500 inside the chamber 116.

Still referring to FIGS. 5 and 6, the inner vessel 500 has a top edge506 with a circumference 507 with a flange 508 extending radially fromthe top edge 506 and one or more recesses 510. The recesses 510 areformed in the flange 508. The flange 508 may extend radially outwardfrom the circumference 506, as shown in this particular embodiment, orradially inward in some other embodiments. The flange 508 and recesses510 are structural elements of the inner vessel 500 that allow the innervessel 500 to be locked inside the pressure cooker 100 by a mechanism tobe discussed in further detail below.

FIG. 4 is an enlarged view of the bottom surface 128 of the outer lid104. An inner lid 310 is secured to the bottom surface 128. The innerlid 310 is the lid that covers the inner vessel 500 when the outer lid104 is closed. The inner lid 310 has an upper surface 312, which arebest shown in FIG. 23, which is an isolated view of the inner lid 310.Several safety and sensing elements are mounted on the inner lid 310.These elements include a temperature measuring assembly 330, a pressurerod 710, and an air-releasing assembly 350, whose structures will bediscussed in further detail below.

Still referring to FIG. 4, a rim 362 is rotatably mounted on the bottomsurface 128 of the outer lid 104. The rim 362 surrounds the inner lid310 and is rotatable in relationship to the inner lid 310. One or morerim protrusions 360 are present at the 362. The rim 362 and rimprotrusions 360 are rotatable clockwise and counter-clockwise. The rimprotrusions 360 form a groove or slot under the rim 362. The slots areformed by the rim protrusions 360 because the protrusions 360 extendoutward from the rim 362 a distance greater than flange 508 of the innervessel 500 before extending down and inward under the rim 310. The rimprotrusions 360 are configured to fit into the recessed portions 510 ofthe flange 508 of the inner vessel 500 so that when the rim 362 isrotated, the flange 508 of the inner vessel 500 slides into the slotformed by each rim protrusion 360 to snuggly secure the inner lid 310 tothe inner vessel 500.

Referring to FIGS. 7, 8, and 9, FIG. 7 is an internal view of theinterior chamber 701 of the outer lid 104 in accordance with anembodiment of the present invention. FIG. 7 shows the upper surface ofthe inner lid 310 and different features and mechanisms of the pressurecooker 100. FIG. 8 is a top internal view of the outer lid 104 and FIG.9 is a side internal view of the outer lid 104.

FIGS. 7, 8, 9, 14 and 15 show an actuator mechanism comprising anactuator rod 700, a handle 106, a locking arm 702, a safety arm 704, anda support plate 312. The outer lid 104 has an interior chamber 701 thathouses the actuator mechanism. The support plate 312 is located withinthe interior chamber 701. In the preferred embodiment, the actuator rod700 is rotatably secured in the center of the support plate 312 andextends upward to pass through an aperture 760 (shown in FIG. 9) in thetop of the outer lid 104. The handle 106 is secured to the top of theactuator rod 700, which makes the handle 104 accessible to the userabove the outer lid 104. The locking arm 702 and the safety arm 704 aresecured to the actuator rod 700 within the interior chamber 701. In thepreferred embodiment, three arcuate slits 716 and 754 are formed in thesupport plate 312 at an approximately equal distance from each other. Aprimary attachment means 752 is secured to the locking arm 702 at aposition on the locking arm 702 that permits the primary attachmentmeans 752 to pass through arcuate slit 754 to be secured to the top ofthe rim 362, which is located below the support plate 312. Thisconfiguration permits the user to rotate the handle 106 in order torotate the rim 362 via the locking arm thereby locking the inner lid 310in place through the engagement of the inner rim protrusions 360 withthe flange 508 of the inner vessel 500 described above.

Focusing on FIGS. 7 and 8, the other two arcuate slits 716 in thesupport plate 312 also have secondary attachment means 714 passingthrough them and are secured to the top of the rim 362, but thesesecondary attachment 714 means are normally not attached to any lockingarm. The two secondary attachment means 714 slide freely in the othertwo slits 716, but include a feature, such as a bolt head or washer oranalogous device, that permits the secondary attachment means to bebiased against the top of the support plate 312 to assist with stablerotation of the rim 362 as the locking arm 702 moves the rim 362 into alocked position. The primary attachment means 752 and secondaryattachment means 714 can be any conventional attachment means such asscrews, bolts, or any other means for securing two elements together.

The safety arm 704 of the actuator mechanism is positioned above asafety channel 764 in the support plate 312. The safety channel 764 ispositioned above a pressure rod 710 that is incorporated into the top ofthe inner lid 310. The safety arm 704 has a member 762 that descendsbelow the safety channel 764 wherein the member 762 can freely movewithin the length of the safety channel 764 if the internal pressure isat a level that is safe for the cooker to be opened. When the pressurein the inner vessel 500 rises to a level that would make it unsafe toopen, then the pressure rod 710 extends into the safety channel 764thereby blocking the safety arm member 762 from moving. Since the safetyarm 704 is secured to the actuator rod 700, this means that the actuatorrod 700 cannot rotate, which effectively prevents the locking arm 702from moving to the unlocked position because the locking arm 702 canonly move in response to rotation of the actuator rod 700. Thismechanism prevents the user from opening the pressure cooker when thepressure inside renders it is unsafe to open.

Still referring to FIGS. 7, 8, and 9, in the interior chamber 701 of theouter lid 104, there are also a temperature measuring assembly 330, apressure rod 710, a reed switch 712 located near the pressure rod 710,an electromagnetic valve assembly 720, and an air-releasing assembly722. The structure of these elements and the interaction of theseelements with other components of the pressure cooker 100 will bediscussed in further detail below.

FIGS. 10-16 illustrates a locking mechanism that simultaneously locksthe outer lid 104 with the main body 102 and locks the inner lid 310with the inner vessel 500. As discussed above, the handle 106, theactuator rod 700, and the rim 362 are connected together. They are allconfigured to have at least respectively a first opened position and asecond closed position. When users turn the handle 106 from the firstopened position to the second closed position, the connection among thecomponents of the locking mechanism will cause the rim 362 to move tothe second closed position, and vice versa. FIGS. 10, 12, 14, 16 showthat the handle 106, the actuator rod 700, and rim 362 are in theirrespective first opened positions. FIGS. 11, 13, 15, 17 show that thehandle 106, the actuator rod 700, and the rim 362 are in theirrespective second closed positions. One of the advantages over manyprior art pressure cookers is that the present invention can be easilyopened and closed with one hand.

Referring specifically to FIGS. 10-13, the outer lid 104 has a claspassembly 800 that includes a spring assembly mechanism 802 that biasesthe clasp assembly 800 in the locked position. The clasp assembly 800 isconfigured to interact with the locking arm 702 when the actuatormechanism moves to the open position such that the locking arm 702applies a force to the clasp assembly 800 to overcome the force of aspring assembly 802 that keeps the outer lid 104 in a locked position.When the clasp assembly 800 is in an unlocked position, then the outerlid 104 may be opened.

At the first open position, the handle 106 via the actuator rod 700 andlocking arm 702 causes the rim 362 to turn so that the rim protrusions360 align with the recesses 510 of the flange 508 of the inner vessel500, thus allowing the inner vessel 500 to be detached from the innerlid 310. The locking arm 702 further causes a clasp assembly 800 to bebiased in an unlocked position. At the second closed position, thehandle 106 via the actuator rod 700 and locking arm 702 causes the rim362 to rotate in the opposite direction so that the flange 508 of theinner vessel 500 slides into the groove of the rim protrusions 360, thuslocking the inner lid 310 on top of the inner vessel 500. When thelocking arm 702 rotates the rim 362 into the locked position, thelocking arm 702 simultaneously disengages the spring assembly 802, whichcauses the clasp assembly 800 to return to a locked position in whichthe outer lid 104 is also locked in place. Hence, both the inner lid 310and outer lid 104 are locked at substantially the same time by a singleaction of the user.

The clasp assembly 800 is movably mounted in the outer lid 104. Theclasp assembly 800 is rotatable vertically along a horizontal axis in alimited degree. FIGS. 12 and 13 show that the clasp assembly 800 isrotated to different possible positions. The clasp assembly 800 restsagainst the spring assembly 802 that pushes the clasp assembly 800 inone direction, such as in the clockwise direction in the particularembodiment shown in FIG. 13. The clasp assembly 800 generally has afirst end 804 and a second end 806. The first end 804 has a hook 852that is best shown in FIGS. 10 and 11. The hook 852 is configured toengage with the locking arm 702 based on the position of the locking arm702. In the preferred embodiment the second end 806 of the claspassembly 800 can be L-shaped, which is best shown in FIGS. 12 and 13.The second end 806 selectively engages with the corner 198 of the mainbody 102. For example, when the clasp assembly 800 is in a positionshown in FIG. 13, the second end 806 is engaging with the corner 198 ofthe main body 102. Since the clasp assembly 800 is located in the outerlid 104, the engagement of the second end 806 and the corner 198 locksthe outer lid 104 and the main body 102 and, thus, prevents the outerlid 104 from being opened.

Referring to FIGS. 10, 12, and 14, the locking arm 702 on one end has aslope 756 (best shown in FIG. 12) and a hook 758 (best shown in FIG.11). When a user turns the handle 106, actuator mechanism causes theslope 756 of the locking arm 702 to engage the first end 804 of theclasp assembly 800 there by causing the first end 804 to ride up theslope 756. When the first end 804 of the clasp assembly 800 reaches itsfinal position along the slope 756, the clasp assembly moves from itsnaturally biased locked position to its unlocked position. As a result,as shown in FIG. 12, the second end 806 disengages with the corner 198so that the user can open the outer lid 104 because the second end 806no longer locks the outer lid 104 with the main body 102.

Now referring to FIGS. 11, 13, and 15, when users turn the handle 106 inan opposite direction, the first end 804 of the clasp assembly 800 ridesback down the slope 756 (best shown in FIG. 13). Hence, the slope 756 isno longer engaging the clasp assembly 800. The clasp assembly 800returns to its natural locked position due to the recoil force of thespring assembly 802. Now, the hook 758 of the locking arm 702 and thehook 852 of the clasp assembly 800 are fully engaged (best shown in FIG.11) and the second end 806 of the clasp 800 and the corner 198 of themain body 102 are also fully engaged (best shown in FIG. 13). Theengagement of the second end 806 of the clasp 800 and the corner 198 ofthe main body 102 locks the outer lid 104 and prevents the outer lid 104from opening. Furthermore, the engagement of the hook 758 of theactuator rod 700 and the hook 852 of the clasp assembly 800 providesadditional locking that prevents the clasp assembly 800 from furthermoving unless the handle 106 turns. This provides additional security sothat the locking of the outer lid 104 does not solely depend on therecoil force provided by the spring assembly 802. This additionalsecurity arrangement allows users to hold the pressure cooker 100 withone hand at the region of the handle 106 without concern that the lockwill not be strong enough and the outer lid 104 will accidentally breakopen.

In summary, FIGS. 10-15 show the interaction among the clasp assembly800, the handle 106 and the locking arm 702. The clasp assembly 800 isconfigured to engage with the locking arm 702 based on the position ofthe locking arm 702. The clasp assembly 800 has at least an unlockedposition, which is shown in FIGS. 10 and 12, and a locked position,which is shown in FIGS. 11 and 13. Since the clasp assembly 800 restsagainst the spring assembly 802, the recoil force of the spring assembly802 naturally biases the clasp assembly 800 in its locked positionunless the locking arm 702 provides a counter-force to resist the springassembly 802 to move the clasp assembly 800 to its unlocked position.

Hence, if a user turns the handle 106 to the position shown in FIGS. 10,12, and 14, the clasp assembly 800 is at its unlocked position and theouter lid 104 is unlocked, allowing the outer lid 104 to be opened fromthe main body 102. If users turn the handle 106 to the position shown inFIGS. 11, 13, 15, the clasp assembly 800 is at its locked position andthe outer lid 104 is locked, thus preventing the outer lid 104 fromopening.

FIGS. 14-17 show the interaction among the handle 106, the actuator rod700, the locking arm 702, the rotatable rim 362, and the inner vessel500. As discussed above, the actuator rod 700 is connected to the rimprotrusions 360 via the primary attachment means 752 so that therotation of the locking arm 702 controls the rotation of the rim 386 andthe positions of rim protrusions 360.

The rim protrusions 360 are configured to selectively engage with theflanges 508 of the inner vessel 500. Referring to FIGS. 14 and 16, whenusers turn the handle 106 in one direction, the handle 106 turns the rim362 via the locking arm 702. At this position, the rim protrusions 360align with the recesses 510 and do not overlap with the flanges 508 ofthe inner vessel 500. Hence, the rim protrusions 360 are not engagingwith the inner vessel 500. As such, the inner vessel 500 can be freelydetached from the inner lid 310. It is noteworthy that the arrangementshown in FIG. 14 is also the arrangement when the clasp assembly 800 isat its unlocked position. Therefore, when the handle 106 is turned tothe position shown in FIGS. 10, 12, 14, and 16, the outer lid 104 can beopened and, simultaneously, the inner vessel 500 is detached from theinner lid 310.

Referring to FIGS. 15 and 17, when users turn the handle 106 in theopposite direction, the handle 106 turns the rim 362 via the locking arm702 to the position shown in FIG. 17. At this position, the flange 508of the inner vessel 500 slides into the groove of the rim protrusions500. This locks the inner vessel 500 with the inner lid 310. The innervessel cannot be detached from the inner lid 310 when the rimprotrusions 360 and the flanges 508 are engaged. Likewise, thearrangement shown in FIG. 15 is also the arrangement when the claspassembly 800 is at its locked position. Therefore, when the handle 106is turned to the position shown in FIGS. 11, 13, 15, and 17, the outerlid 104 is locked and, simultaneously, the inner vessel 500 is alsolocked with the inner lid 310. The locking between the inner vessel 500and the inner lid 310 provides additional protection to prevent theouter lid 104 from being opened from the main body 102.

When the inner vessel 500 is locked with the inner lid 310, the innervessel 500 is sealed. This allows pressure to be built up duringcooking. The locking mechanism of the handle 106 not only locks theouter lid 104 with the main body 102, but also seals the inner vessel500 for cooking. As such, these interactions among the handle 106, theactuator rod 700, the locking arm 702, the clasp assembly 800, the rim362, the rim protrusions 360 and the flange 508 of the inner vessel 500provides a locking mechanism that can be operated with one hand tosimultaneously lock the outer lid 104 with the main body 102 and lockthe inner lid 310 with the inner vessel 500.

Now referring to FIGS. 18, 19, 20 and 23, these figures illustrate apressure indicator mechanism for the pressure cooker 100 in accordancewith an embodiment of the present invention. The inner lid 310 istraversed by a pressure rod 710. The pressure rod 710 provides anindication of the level of pressure in the inner vessel 500. Thepressure rod 710 is integrated with the inner lid 310 so the pressurerod 710 is able to traverse the inner lid 310 but not be removed fromthe inner lid 310. The pressure rod 710 can incorporate any conventionalmethod for responding to pressure such as providing calibrated weightresistance or other calibrated biasing means to respond to respond topressure within the inner vessel 500. The pressure rod 710 is configuredso that it is pushed upward by pressure within the inner vessel duringcooking.

In one embodiment shown in FIGS. 18-20, the pressure rod 710 isconnected to a pressure indicator 112. The pressure indicator 112protrudes outside of the outer lid 104 such that the pressure indicator112 is visible to the users when the outer lid 104 is closed. Whenpressure is built up in the inner vessel 500, the pressure pushes thepressure rod 710 up. In turn, the pressure rod 710 pushes the pressureindicator 112 up. Since the pressure indicator 112 is visible, the riseof the pressure indicator 112 provides indication to the users thatpressure has reached a certain level inside the inner vessel 500. Howthe change in pressure inside the receptacle 500 affects the positionsof the pressure rod 710 and the pressure indicator 112 is illustrated bythe differences between

FIG. 19 and FIG. 20.

In an alternative embodiment, the pressure rod 710 and the pressureindicator is a single piece. A portion of the pressure rod 710 protrudesoutside of the outer lid 104 such that a portion of the pressure rod 710is visible to the users when the outer lid 104 is closed. The pressureindicator mechanism is essentially the same as the embodiments thatcontains separate pressure rod 710 and pressure indicator 112.

In some embodiments, the pressure rod 710 also comprises a firstair-releasing opening 792 and a second air-releasing opening 794. Insidethe pressure rod 710, there is an air-passage channel 796 that connectsthe first air-releasing opening 792 and the second air-releasing opening794. The first air-releasing opening 792 is located above the uppersurface 312 of the inner lid 310 and the second air-releasing opening794 is located below the lower surface 314 of the inner lid 310. Assuch, air is free to go in or out of the inner vessel 500 unless atleast one of the air-releasing openings is blocked by some means. Inother words, when both of the air-releasing openings are open, pressurecannot build up within the inner vessel 500 because the inner vessel 500is not completely sealed. In order to build up pressure in the innervessel 500, one of the air-releasing openings must be closed or covered.For example, in FIG. 19, the first air-releasing 792 is covered by acircular wall 7106 thereby permitting pressure to rise when the pressurerod 710 is in this configuration.

FIGS. 8, 19, and 20 illustrate a safety feature that is related to thepressure rod 710 in accordance with an embodiment of the presentinvention. Referring to FIG. 8, the pressure rod 710 is located near thesafety channel 764 and the member 762. The pressure rod 710 isconfigured to interact with the member 762. The pressure rod 710traverses the inner lid 310 and it is configured to move to differentlevels. In one embodiment, the pressure rod 710 is capable of being at afirst opened level or a second closed level. When the handle 106 is atits first opened position, for example, the position shown in FIG. 10,12, or 14, the safety arm 704 is also at its first opened position. Whenthe safety arm 704 is at its first opened position, the pressure rod 710is configured such that the pressure rod 710 will remain at the firstopened level such as the level shown in FIG. 20. At the first openedlevel, as shown in FIG. 20, both the first air-releasing opening 792 andthe second air-releasing opening 794 are open. This prevents thepressure in the inner vessel from being built up.

When the handle 106 is at its second closed position, the position shownin FIGS. 11, 13, 15, the safety arm 704 is also at its second closedposition. This allows pressure to build, which can result in thepressure rod 710 moving to the second level. At the second level, asshown in FIG. 19, the first air-releasing opening 792 is covered by thewall 7106. Hence, the air-passage channel between the firstair-releasing opening 792 and the second air-releasing opening 794 isblocked. This allows the pressure in the inner vessel to rise. While inthe embodiment shown in FIG. 19 it is the first air-releasing opening792 that is blocked, those skilled in the art will understand that inother embodiments it could be the second air-releasing opening 794 thatis blocked at the second level or even both air-releasing openings canbe blocked at the second level. Those skilled in the art will alsounderstand that the location of the first air-releasing opening 792 andthe second air-releasing opening 794 are interchangeable.

The interaction between the pressure rod 710 and the safety arm 704provides a safety mechanism to prevent the pressure cooker 100 frombeing opened when under pressure. When the safety arm 704 is at itsfirst opened position, the outer lid 104 is not locked with the mainbody 102 and the inner vessel 500 is not locked with the inner lid 310.The pressure rod 710 remains at the first level when the actuator rod700 is at the first opened position. The air-releasing openings of thepressure rod 710 prevent pressure from building up. This insures thatthe pressure cooker 100 cannot build up pressure even if the pressurecooker 100 is turned on if it is not fully locked. When the handle 106is turned to the second closed position, the components of the pressurecooker 100 are locked. The pressure rod 710 is at the second level andthe wall 7106 blocks the first air-releasing opening 792. In thisconfiguration, the pressure cooker 100 is ready to be used and pressurecan be built up in the inner vessel 500.

One safety concern of pressure-cooking is that users accidentally openthe lid of a pressure cooker when the pressure cooker is under highpressure. This will create a rapid expansion of hot gas that could causesevere injury to the users and even explosion. FIGS. 21 and 22illustrate an additional safety mechanism of the pressure cooker 100 inaccordance with an embodiment of the present invention. As discussed,the pressure rod 710 is configured to move upward when the pressure ofthe inner vessel 500 builds up during cooking. In one embodiment, thepressure rod 710 is located in the rotating path of the safety arm 704.

In an alternative embodiment, the safety channel 764 is positioned rightabove the pressure rod 710, as shown in FIG. 10. When pressure is low,the level of the pressure rod 710 is below the rotating path, as shownin FIG. 21, or the safety channel 764, as shown in FIG. 10. Thus, thehandle 106, the locking arm 702, and the safety arm 704 are all free torotate between the first opened position and the second closed position.When the pressure in the inner vessel rises to a level that would makeit unsafe to open, then the pressure rod 710 extends into the safetychannel 764 thereby blocking the safety arm member 762 from moving.

Alternatively, the pressure rod 710 is configured such that it is pushedupward to a third level and a portion of the pressure rod 710 exceedsthe upper surface 312 of the inner lid 310. Now a portion of thepressure rod 710 is in the middle of the rotating path of the safetychannel 764. The pressure rod 710 blocks the path and prevents thesafety arm 704 from turning to the first opened position. Since thesafety arm 704 is secured to the actuator rod 700, this means that theactuator rod 700 cannot rotate, which effectively prevents the lockingarm 702 from moving to the unlocked position because the locking arm 702can only move in response to rotation of the actuator rod 700. As such,after cooking and when the pressure in the inner vessel 500 is at acertain high level of pressure, the lids of the pressure cooker 100cannot be immediately opened because a portion of the pressure rod 710is blocking the safety arm 704 from turning to the first openedposition. The user must wait until the internal pressure returns to asafe level before the handle 106 can be turned to open the pressurecooker 100. This mechanism prevents the user from opening the pressurecooker when the pressure inside renders it is unsafe to open.

Referring back to FIG. 18, in one embodiment of the present inventionthe pressure rod 710 also comprises a component of magnetic material7108 mounted on the pressure rod 710. Since the change in pressure ofthe inner vessel 500 changes the position of the pressure rod 710, thepressure rod 710 in turn carries the magnetic component 7108 todifferent positions. A reed switch 712 is located in the proximity ofthe pressure rod 710. The reed switch 712 is configured to control theelectrical circuit of the pressure cooker 100 and is also configured todetect the location of the magnetic component 7108 based on the changeof magnetic field due to the different locations of the magneticcomponent 7108. The reed switch 712 changes the electrical circuit basedon the position of the magnetic component 7108. For example, the reedswitch 712 can be configured such that, when the inner vessel 500 is ina high pressure and the pressure rod 710 is pushed up, the reed switch712 provides an indication to the user interface 110 to visually signalthe users that the pressure cooker 100 is in a high pressure. Also, ifthe pressure of the inner vessel 500 is at a dangerously high level, thereed switch 712 detects that the pressure rod 710 is pushed up to a veryhigh level. The reed switch 712 can be configured such that at thisstage the reed switch 712 will cut off the circuit of the pressurecooker 100 to prevent pressure to further build up.

FIG. 23 is an isolated view of the inner lid 310 together with the rim362 in accordance with an embodiment of the present invention and FIG.24 is an exploded view of the inner lid 310 and the rim 362. As shown inFIG. 24, the rim 362 is surrounding the inner lid 310 and the rim 362 isrotatably mounted about the inner lid 310. Both components are mountedon the outer lid 104 when installed. An air-releasing assembly 350 and apressure rod 710 are located on the surface of the inner lid 310. Therim 362 is rotatable in relationship to the inner lid 310 and is securedto the locking arm 702 and outer lid 104 through attachment means 752and 714 (best shown in FIGS. 7 and 8). When the inner lid 310 isinstalled in the pressure cooker 100, the rim 362 is rotatable and iscontrolled by the handle 106 via the locking arm 702 by the mechanismdescribed in detail above. When the rim 362 rotates, the inner lid 310remains stationary in the preferred embodiment.

Referring to FIG. 25, in accordance with an embodiment of the presentinvention, the pressure cooker 100 has two different ways to control orrelease pressure of the inner vessel 500. The first way is through theair-releasing openings 792 and 794 of the pressure rod 710 as discussedabove. The second way is through an air-releasing assembly 350. In thisembodiment, the pressure cooker further comprises an electromagneticvalve 358. The inner lid 310 has an air-releasing assembly 350 mountedon its upper surface. An air-releasing conduit 352 is present within theair-releasing assembly 350. The air-releasing conduit 352 traverses theinner lid 310 such that air can go in or out of the inner vessel 500through the air-releasing conduit 352. A ball bearing 354 is movablymounted within the air-releasing assembly 352. The ball bearing 354 hasa sealed position and a released position. The air-releasing conduit 352cannot release pressure from the inner vessel 500 when the ball bearing354 is at the sealed position, and can release pressure when the ballbearing 354 is at the released position. When the ball bearing is at thereleased position, it is configured to be pushed slightly away from theaxis of the air-releasing conduit 352, thus opening the air-releasingconduit for air to be released from the inner vessel 500.

The electromagnetic valve 358 controls the position of the ball bearing354 such that the electromagnetic valve 358 can control the pressure ofthe inner vessel. The electromagnetic valve 358 is coupled to a push rod356. The electromagnetic valve 358 controls the position of the ballbearing 354 by applying a electromagnetic field to the push rod 356. Forexample, the default position of the ball bearing 354 is the sealedposition. The users can control the release of pressure of the innervessel 500 through the user interface 110. When the user interface 100receives the command from the user, it directs the electromagnetic valve358 to generate an appropriate magnetic field that causes the push rod356 to push forward, pushing the ball bearing 354 away from the axis ofthe air-releasing conduit 352, thus allowing air to be released from theinner vessel 500.

In an embodiment of the present invention, the pressure cooker 100 isconfigured such as the release of pressure is automatic after cooking.As discussed, after cooking, the inner vessel 500 is at a high pressureand the pressure rod 710 is pushed up, thus blocking the rotating pathof the actuator rod 700 and preventing users from opening the lids. Atthis stage, the reed switch 712 provides an appropriate signal to thecircuit and directs the electromagnetic valve 358 to cause the ballbearing 354 to move from the sealed position to the released position.In turn, air is slowly released from the inner vessel 500 and thepressure rod 710 is lowered. After the pressure rod 710 is lowered to acertain level, the reed switch 712 detects that the pressure rod 710 islow enough that it no longer blocks safety arm 704. The reed switch 712then causes the user interface 110 to signal, such as by sound or lighton the display of the user interface 100, to the user that the pressurehas been lowered to a safe level for the user to open the pressurecooker 100. Then the user can turn the handle 106 to open the outer lid104 after this automatic air-releasing mechanism.

Referring to FIGS. 27 and 28, the pressure cooker 100 has specialstructure for steam to be released from of the pressure cooker 100 andfor condensed water to be collected together. The outer lid 104comprises a steam valve 114 with external steam release openings 904 onthe steam valve 114. The outer lid 104 also comprises a passage 906which is connected to the external steam release openings 904 at a firstend and configured to communicate with the air-releasing assembly 350.Hence, steam or air that is released from the air-releasing assembly 350will exit the pressure cooker 100 via the passage 906 and the steamvalve 114.

The passage 906 has a floor 908 that is sloped toward the air-releasingassembly 350 and the passage 906 is connected to a water storage cup910. For any water that is condensed when the steam is passing throughthe passage 906, the water will go down along the slope of the passage906 to be collected in the water storage cup 910. If excessive amount ofwater is generated, the slope of the passage 906 will make sure that thewater will go back via the air-releasing assembly 350 to the inner lid310. In this way the condensed water will only go to certain locations.This prevents water from going to other undesired location such onkitchen surface on which the pressure cooker 100 is operated. As such,the pressure cooker 100 is cleaner to use. The steam valve 114 and thewater storage cups 910 are removable for cleaning purpose.

Now referring to FIG. 29, it is an internal view of the pressure cooker100 in accordance with an embodiment of the present invention. Below thechamber 116, the pressure cooker 100 further comprises a heatingassembly 180. The heating assembly 180 can be any type of heatingcomponent known in the art such as heating coil or magnetic heatingcomponent. At the upper middle region of the pressure cooker 100, thereis a temperature measuring assembly 330 that measures the temperatureinside the inner vessel 500. The temperature measuring assembly 330 canbe of any type known in the art such as a negative temperaturecoefficient type temperature component.

The pressure cooker 100 also comprises a user interface 110 and a mainprinted circuit board assembly 182, which allows users to electricallyor digitally control the pressure cooker 100 via the user interface 110.The circuit board assembly 182 is configured to communicate with theelectrical or electronic components of the pressure cooker 100, such asthe temperature measuring assembly 330, the reed switch 712, theelectromagnetic valve 358, the heating assembly 180, and the cooling fanassembly 184. As such, users can control the temperature and pressure ofthe pressure cooker 100 via the user interface 110 and obtaintemperature and pressure information from the display of the userinterface 110. For example, the users can control the release ofpressure inside the inner vessel 500 by controlling the electromagneticvalve 358 to push the ball bearing 354 to the released position at anytime. The user can also adjust the temperature of the pressure cookerthrough the user interface 110.

While in some embodiments discussed above the handle 106 is configuredto be turned by the user manually, in other embodiments the handle 106is connected to a motor that is controlled by the circuit board 182. Assuch, a user not only can turn the handle 106 to open or lock the lids,but also can use the user interface 110 to control the motor to turn thehandle 106. As such, the opening and locking of the lids can be achievedautomatically through the communication among the user interface 110,the circuit board 182 and the motor of the handle 106.

In some embodiments, the user interface 110 also has a wirelesstransceiver that is configured to utilize wireless technology such asBluetooth or Wi-Fi to communicate remotely with users. As such, the userinterface is capable of being controlled remotely to carry out anyfunctions that are described above.

The foregoing description of the embodiments of the present inventionhas been presented for the purpose of illustration and description. Itis not intended to be exhaustive or to limit the invention to theprecise form disclosed. Many modifications and variations are possiblein light of the above teachings. The numerical values described in thedescription are only for illustration purpose and should not beunderstood as limiting the invention to the precise numbers. It isintended that the scope of the present invention not be limited by thisdetailed description, but by the claims and the equivalents to theclaims appended hereto.

I claim:
 1. A cooking device, comprising: a main body with a chambertherein; an outer lid being pivotally mounted on the main body such thatthe outer lid can be opened or closed relative to the main body; aninner vessel which is configured to be removably placed within thechamber; and an inner lid on the outer lid the inner lid beingconfigured to cover the inner vessel when the outer lid is closed; apressure rod is movably secured on the inner lid such that the pressurerod is configured to be able to traverse the inner lid but not beremoved from the inner lid; wherein the pressure rod is configured to bepushed upward by the inner vessel's pressure during cooking; and,wherein the pressure rod further comprises a first air-releasing openingand a second air-releasing opening that are configured to allow air togo from one air-releasing opening to another.
 2. The cooking device ofclaim 1, wherein the pressure rod is connected to a pressure indicator,which is protruding outside the outer lid, such that the pressureindicator is visible when the outer lid is closed in relative to themain body.
 3. The cooking device of claim 1, wherein the pressure rod isconfigured to be positioned at least at a first level and a secondlevel; at the first level both the first air-releasing opening and thesecond air-releasing opening are open, thus preventing the innervessel's pressure from being built up; at the second level the secondair-releasing opening is covered, thus allowing the inner vessel'spressure to be built up.
 4. The cooking device of claim 1, furthercomprising an actuator rod that is rotatable and a handle that isconnected to the actuator rod.
 5. The cooking device of claim 4, whereinthe pressure rod is configured such that, at a certain pressure, thepressure rod is pushed upward and a portion of the pressure rod exceedsthe upper surface of the inner lid; and wherein the portion isconfigured to prevent the actuator rod from rotating.
 6. The cookingdevice of claim 1, further comprising: an electrical circuit controlledby a reed switch; a component of magnetic material mounted on thepressure rod such that the pressure rod carries the magnetic componentto different positions; wherein the reed switch is configured to changethe electrical circuit based on the position of the magnetic component.